Absolutely nothing is sexual about a young girl wearing a bikini. If you really broke down the argument that they shouldn't be wearing child versions of adult clothes
Do your small daughters wear push-up bras? Stockings and suspenders? High heels?
Whoever this was who replied to me missed out the bit that said "the argument falls apart" about children wearing adult clothes.
Historically, children were dressed like adults. There is absolutely nothing new about this. Children (boys) incidentally also wore high heels at one point. Girls wore corsets - a lot like push up bras - from an early age. Stockings were held up by suspenders and buttons. Dresses and suits were just scaled down versions of adult ones.
Some things quite rightly have gone for medical reasons (corsets!) but let's get over the idea that this is a new thing, or something shocking. It's not. As fashions change, kids clothes change too.
Take an easy example like children wearing ties to school... it's absolutely not necessary, it's frankly a bit weird when you think about it, especially putting girls in them when women don't wear them.
Why do we put little boys in bow ties at weddings? Or waistcoats? Or kilts?
Why do women's and kid's jeans have flies when clearly we don't use them like men do and there are other ways to fasten up trousers in other styles?
Why do baby boy trousers often have a fake sewn up fly? Surely the most pointless extra detail 😂
Any style of bikini is fine OP in my opinion. And no man has the right to say what his granddaughter wears 🙄