4 year old wetting pants.

I am at my total wits end. So please for giveme if this rambles a bit. My
dd is 4 years old and has taken to wetting her pants.. She had quite a while
where we were doing GREAT we were even having quite a few dry nights .. so
much that she was wearing panties to bed rather than training pants.
But recently things have taken a drastic change. I have a feeling it's
related to dh going out to sea and ds being born in Dec. I have tried giving
her more attention, time outs you, loss of prilidges, treating her for
going, you name it.. nothing works it's almost like she doesn't care. I
don't know what else to do.

Example. SHe would go with me to all my pre natal appointments, One in
particular she wet herself on the way there. I changed her, and went in. As
we were waiting to be called she said she had to go, so we went to the
bathroom an she went. Then while we are in with the doctor, she doesn't
bother even saying anything and proceeds to wet her pants not even 20 mins
after I had just taken her to the bathroom ..

I have had to take to putting her in pull ups when we go run errands or else
I would have to take numerous changes of clothes; which to her seems to be
permission just to go ahead and pee since she doesn't feel it. Not that we
pants seems to bother her too much either.

I have even caught her intentionally pulling down her pants and going on the
floor just so she wouldn't get in trouble for getting her pants wet. So I
know she knows when she has to go. Granted our only bathroom is upstairs but
this is gettiing rediculous.

I have no idea what to do. PLEASE HELP!!

Kylee