"It's stupid," he said.
I asked him his favourite song, expecting him to name the theme tune to his favourite television programme. "I'm sexy and I know it," he sang animatedly, referring to the hit LMFAO song.
I was horrified. Surely an eight-year-old shouldn't be singing about trying to "tan my cheeks" or having a "passion in my pants", never mind proclaiming himself sexy?
I was equally as mortified at a birthday party where the soundtrack to Pass The Parcel was Kings Of Leon's Sex On Fire, after the parents left their iPod on shuffle.
Don't get me wrong, it's a fantastic song – just not in a room full of under fives.
Mum-of-one Louise shares my concerns. She was shocked that her friend's four-year-old daughter knew all the words to songs by Lady Gaga. "That's a little young and worrying," she says.
"My friend was very proud of it and would encourage her by playing the radio and music channels as much as possible. I am pleased that my daughter only sings nursery rhymes and Cinderella and Tangled songs. I can live with Disney."
My friend Kelly thinks I'm prudish. She and her husband regularly go to gigs and festivals, and her children, Caitlin, 8, and Dylan, 5, love dancing around to the music channels.
"I want my kids to be exposed to as many different genres of music from an early age and I hope they develop my love for music," she says.
"I have never censored anything mainstream that might come on the radio or the music channels. I am slightly more careful about CDs or downloads that have explicit lyrics but don't stress that much about the odd rude word."
Her daughter attends street dance classes three times a week. "The music she dances to is pretty raunchy sometimes," says Kelly. "I don't think it has any impact on behaviour or growing up too quick, it's just music."
She believes children don't understand half of what they are listening to in any case. "One of Caitlin's favourite songs is Sex On Fire, but she thinks they're singing sax on fire, as in saxophone," she says.
"It makes me laugh. I think that to her young, innocent mind the words in these songs don't mean anything and making a point of it by banning songs draws more attention to it."
Mum of two daughters, Aimee, feels the same. Her eldest, aged four, loves singing the 'Hey, sexy lady' refrain from Gangnam Style.
"I'm not bothered as I know she hasn't a clue what it means yet," she says. "I will censor if she ever starts gyrating sexily to it though!"
They have a point. I remember singing to Madonna's Like A Virgin before I knew what one was, and I never thought to question it. And as my friend Nicola, pregnant with her second child, reminds me, nursery rhymes are often just as inappropriate as pop music.
"Most nursery rhymes and lullabies are quite dark if you listen to the lyrics," she says. "Rockabye Baby is very dark"
Indeed, who wants to think about babies and cradles falling out of trees, or Goosey Gander throwing an old man down the stairs, or mice having their tails cut off with carving knives?
So, what's the solution? Life coach Eve Menezes Cunningham suggests talking to older children about the lyrics or what they see on screen in music videos "to help them understand the messages and figure out their own responses".
She says, "Even if you never have it on at home, they'll be exposed elsewhere. Having an adult talk to them about it and find out how THEY feel when they watch, for example, endless images of men looking powerful while scantily clad women gyrate as if they're available, might help them make sense of it."
My husband and I have figured that exposing our children to music doesn't have to mean exposing them to age-inappropriate content. We have found a happy medium with carefully-compiled playlists of music we enjoy, which we hope will give them a musical education as well as saving us from having to endure endless rounds of The Wheels On The Bus during long car journeys or at children's birthday parties, which is where we spend most of our weekends these days.
Our playlist includes everyone from The Beatles, Queen and The Beach Boys to Oasis, Feeder and The Prodigy, with plenty of Madonna, Take That and even the Dirty Dancing soundtrack (my choices, not my husband's, he would like me to add!).
Fortunately, our little ones are still young enough not to automatically think the music their parents like is un-cool. When that happens, we might have to re-evaluate our in-car music policy but in the meantime, here are a few of our favourites.
Great for family-friendly car journeys:
The Beatles – Nothing beats the innocent, happy-go-lucky loveliness of the Fab Four's early hits (and some of their later ones too): I Want To Hold Your Hand, Love Me Do, Yellow Submarine, Ob-La-Di, Ob-La-Da, Here Comes The Sun.
Queen – Upbeat, sing-a-long rock with attitude and fun: Don't Stop Me Now, We Will Rock You, You're My Best Friend, We Are The Champions. You might want to skip Bohemian Rhapsody and its talk of having just killed a man though!
Oasis – Despite their wild ways, a lot of the lyrics are innocent enough: Wonderwall, Live Forever, Whatever, are all great to sing along to.
Madonna: She's the Queen of Pop so your children should know who she is. Avoid her raunchier material in favour of the catchy Material Girl, Vogue, Like A Prayer, and Holiday.
Fleetwood Mac – Your own parents will enjoy this as much as your children. They're currently touring again so what better time to dust off this classic?. We like Go Your Own Way or Everywhere.
Perfect birthday party playlist:
Walk Like An Egyptian by The Bangles – They study Egypt at school, so this one is educational, right?
Livin' On A Prayer by Bon Jovi – This was a staple at my school discos and it's just as energising today.
Dynamite by Taio Cruz – You know you want to throw your arms up in the air and say ay-oh. Just make sure you have the censored version.
Hey Mickey by Toni Basil – My daughter thinks this is about Mickey Mouse.
99 Red Balloons by Nina – Even better if you have red balloons scattered around the room.
Wake Up Boo by The Boo Radleys – Such a happy, vibrant and catchy song.
Firework by Katy Perry – subtly instilling confidence with lyrics including "even brighter than the moon, moon, moon and it's always been inside of you".
Money by Jessie J – More positive brain-washing: "We don't need your money, money, money. We just wanna make the world dance."
Spinning Around by Kylie Minogue – children will love twirling around while the dads will be thinking of those gold hot pants. Also try The Locomotion; the children will love joining up to form a train.
That's What Makes You Beautiful by One Direction – Girls of all ages will adore this ode to natural beauty.
ABC by The Jackson 5 – again, 'educational' but oh-so-catchy and an absolute classic.
500 Miles by The Proclaimers – we know you love to hate this one but it's great to jump around to.
Never Forget by Take That – cue much discussion among mums about whether we prefer the old or new stuff, who's the fittest now and back then.
Jump (For My Love) by The Pointer Sisters – little ones will enjoy jumping as high as they can to this one.
Out Of Space by The Prodigy – such fun pretending you're dancing around in space.
Happy Birthday by Stevie Wonder – for obvious reasons.
What would be on your list? What songs are your family favourites?