Will start this by saying I had some pretty full-on postnatal anxiety after having my DD and am still working on anxiety now, so worried my concerns here may be unnecessary... 
but would welcome any input.
I've been a bit worried about my 15mo DD seeming to daydream quite intensely. She seems to stare at a fixed point, most of the time doesn't respond to me saying her name a few times. Stare is usually broken by me holding a hand in front of her face (she usually cranes her neck round if I do!). It only ever seems to happen in her high chair, where she does get very bored and hates being in as she's really enjoying being able to run and walk around perfectly now.
Anyway, I noticed it a bit but tried not to worry too much. But my sister has made a comment on it when she was sat next to her last time we saw her (DD again was in her high chair) and made a point of saying so. Her son has absence seizures very frequently so I've taken this quite to heart and been worried sick watching out for them ever since...
I'm thinking it's best to take her to the GP and mention them. My DH thinks I'm overreacting, that she usually moves around us if our hands are in front of her, they're not the same as my DN's and that they ALWAYS have happened in her highchair and she's just daydreaming/bored. But isn't 15mo too young for daydreaming?
Any advice really appreciated, thank you!