Daddy and Bath

Last night Annabelle was trying out her signs. She spent the whole day with daddy as is the norm for her on Fridays and when I came home he left to go out. She doesn't usually cry when he leaves but she has been having a lot of separation anxiety the past few weeks. When he left she started crying and I took her to the window so she could wave bye-bye. She loves looking out the window and we stood there for awhile and she waved and watched him pull out.
A few hours later I said something about Daddy. She turned towards me and did her sign for BATH. I have seen her do this when she wants to take a bath or if Daddy is in the shower. I thought she would start going up stairs to the bathroom but instead she went back to the window and started saying "dada." I told her Daddy would be home later.
Later on she tried to do the sign for WINDOW again and started saying "dada." I had to take her back to the window and let her wave "bye bye" to Daddy some more even though he had left hours earlier.
I am trying to figure this out. Maybe she is associating the sign with BATH with daddy because he usually gets in the tub with her in his swim trunks or when he says Daddy he hits his chest like she was doing. Either way she was trying to communicate and did so with some success. I don't think she would have been able to do so without the use of sign language.