A Bay is a VERY likely outcome from a sorrel and black paint pairing. If neither parent is Homozygous for a paint patterned gene, then the foal could very well come out as a Solid baby but what I see and hear, she looks too big to only be 5 months along and it would mean she was bred in October and a breeding in October at all is fairly Rare(In Northern Hemisphere).
Lena is Gorgeous though! Can't wait to see her filled out with a healthy foal next to her! I hope it comes out looking half as gorgeous as momma and Daddy!
By the way, He's a Medicine Hat Overo.
And -nudge nudge- this was still in my Inbox from when you sent it to me a couple days ago