this has happened to me too. (and yes i have av3!). I type in my correct username, then type in the correct password from my family list, and it says incorrect! The first few times I thought I was typing it wrong, but I wasn't! I think there might be a certain limit to how many times you can visit your parent...
Maybe... you can't visit your parent after you are an adult! Cus I had just turned into an adult when this started happening!
Ally