And how old are they?
My 3.5 year old uses swimmies and has a puddle jumper. She alternates depending on her mood.
My 1.5 year old still is just held or put in a baby float. She's SO petite I can't find anything small enough, but she's also very independent and busy and I'd love to let her learn to swim a bit with adult help. She's barely 19 lbs wet, so I don't see her fitting in a puddle jumper for years.