Shopping for a first bra is an important milestone for any girl, but it can be difficult to know when the time is right to take her for a fitting.
Some girls are desperate to wear one, especially if their friends already have them, while others try to put if off for as long as possible.
What's more, some parents feel understandably uncomfortable about buying a bra for their little girl, especially if she's under 10.
It doesn't help that several retailers have been criticised for selling overly sexy undies to pre-teens, so we worry about finding a style that's both comfortable and age appropriate.
Whatever the situation, it's important to handle it sensitively - as this is an experience that your daughter is likely to remember forever.
Some teenagers are nervous about going to buy their first bra
"I found the whole experience so embarrassing," says Sally, 38. "I was 11 when my mum took me to a department store where this old woman measured me, laughed at my flat chest and handed me an ugly, itchy, padded bra to try on.
"I hated it and hardly ever wore it."
Bear in mind that if your daughter is already in her teens, she'll want to fit in with her friends - so, if she asks to go bra shopping, don't dismiss her request if she doesn't yet need to wear one.
"When I was 12, my mum said I didn't need a bra yet," says Luanne, 30.
"But all the girls in my class had them and you could see them through their school blouses. Mum fobbed me off with crop tops for a while, but at least I got rid of the vests!"
So how do you know when your daughter actually needs to start wearing a bra?
"The average age to start wearing a bra is 11, but some girls need one from the age of nine, while others don't need one until they are 14," says Maria Law, co-founder of Sweetling.co.uk, a company which designs and makes comfy first bras for girls.
"Comfort is the main reason for buying a first bra," adds Sophie Law, also from Sweetling. "As breasts develop and get bigger they can feel tender and sometimes a little painful.
"Wearing a good quality, well-fitted first bra should alleviate some of the discomfort and can also stop any embarrassment caused by nipples showing through tops or breasts moving around when walking or running."
When it comes to choosing a first bra, there are a few things to consider.
It's a good idea to introduce a crop top to begin with, around the time that the nipples start to protrude from the chest. When breast tissue starts to develop, that's the time to move to a soft cup bra.
Avoid underwired bras as these can interfere with the development of breast tissue - and remember to buy at least two to allow time for washing and drying.
If your daughter is embarrassed about being fitted in a shop, you can make the experience more comfortable by measuring yourself at home and ordering online.
Sweetling has a useful measuring guide, which makes it easy to work out the correct size - and is a good way to gauge if your daughter is really ready.
"If she is ready for our first 'starter bra', her size will show up on our measuring page," says Maria.
"If not, suggest that she keeps wearing a crop top until her breasts tissue has developed a little more. Measure every four weeks until the time is right - starting this process should help to make her feel more comfortable about the prospect of getting her first bra."
Getting your teenager fitted with a proper bra is very important
Most importantly, although a bra might feel strange, it should not feel uncomfortable.
"A proper fitting teen bra is very important," says Maria.
"When breasts develop they need to be lightly supported so that they can grow into their natural shape and position. If a first bra doesn't fit right, then it isn't doing it's job and will be uncomfortable."
Handle it right, and buying your daughter's first bra can be a fun experience for both of you.
"I took my daughter bra shopping just before she started year seven," says Clare.
"We talked about it over the summer holidays and decided to turn it into a bit of a celebration, so we had a day out shopping, she was fitted in a department store, and we went out for lunch. It was a lovely day and we both found it all quite exciting."
But that approach doesn't work for everyone.
"My daughter is a tomboy and wore lots of baggy tops to hide the fact that she needed a bra," says Emma.
"When she turned 12, I realised that we couldn't put it off any longer, so I ordered a few different styles and sizes online and let her try them on by herself to see which one she liked best.
"I would have liked to be more involved, but I didn't want to make her uncomfortable. Fortunately, she told me when they were getting too small and that's when I took her to be properly fitted."
Finally, don't be surprised if you feel a little bit sad - breast development is often one of the first signs of puberty and is a sure sign that your little girl is growing up.
But it's important to let her know that this is all very normal and natural so that she won't feel self-conscious or ashamed of her changing body.
When did your daughter want or get her first bra? Let us know in the comments below!
Many high-street retailers will sell specific "my first bra" packages for girls.
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