obsessive behavior

Question
I have 5 chihuahuas.  Recently the youngest who is 2 years old found an old toy and it has become her life.  She is making my husband and I crazy  She runs around with it in her mouth and if I take it away from her she runs around frantic and crying.  She has never exhibited this behavior before  She has become slightly aggressive to the other dogs for fear they may take it.  Actually noone has any interest in it but, they have all become afraid of her.  What can I do ?  She is very stressed over it and so are we.

Waiting for your reply
Ellen

Answer
My first question to you would be; is she spayed? If not, then she might be having a false pregnancy which will cause her to act this way.

If she isn't spayed, you need to get her to the vet's asap and get her taken care of. Her aggression will not get better until this is resolved.

It is very uncommon for a spayed dog to behave this way, even at 2 yrs old.

Make an appointment and have your vet look her over and get her spayed.