Is there a religious/cultural reason why families will dress their kids to match?

Hi there, non jew here. Hope it’s okay to ask. I’m a flight attendant at an airport that services a large population of Jewish folk (we fly to tel aviv and El Al flies out of here). I’ve noticed a lot of Jewish families will have their kids in identical clothing. Is there a particular reason for it?

Edit, forgot to say, thank you, have a nice day!