I would of worried about Sunshine's soon to be foal. I wouldn't be introducing a new horse with a baby on the way at all. God only knows what kinds of conditions it might expose the foal too. A good friend of mine just lost her yearling filly to bloodworms because a "friend" put a "rescue" in the pasture with her filly. Turns out the rescue was full of bloodworms and got into her filly. Her and the vet tried all they could once they found out the actual problem, but it was too late.