Can i obtain records of what IP Address accessed my yahoo email account and forwarded my emails ...?

my wife and I are in a dovirce/custody battle.She took my Son 1000 miles away from me,and I had no contact with him for 4 mths because she would not allow it.I got a court oredered 20 day visitation with him.I thought that if I made photos and video of him available to her that she may thaw a bit and allow me photos and video of my son.So I created a yahoo email account for her to access pics and videos I attached and emailed to myself.After I returned my son to her,I had posted a few journal entries as Letters To My Son.She went into my email account and read tehm and then forwarded them to herself.She has turned the emails over to her attorney claiming that I emailed them to her.THis is a lie.We have a mutual restraining order.She is trying to have me arrested for something that she did.Can Yahoo provide me with records of the IP Addresses that have accessed my email account and forwarded emails from it?How would I obtain this information?