Not eagles, but an interesting situation with a red tail hawk nest that has a cam in Philadelphia.

The male hawk was killed by a car recently, and supplemental food is being provided to help the female care for her family. To everyone's surprise, another hawk, presumably male, has turned up and is even assisting (a little) with feeding the young.

We had a similar situation in NYC which I watched very closely last year, and the female tolerated NO hawk visitors until long after her kids were grown and on their own.

A very good blogger covers the Philadelphia nest.

By the way, the consultant for this cam is a falconer and he insists everyone use falconry terms (tiercel for male, haggard for adult, and formel, a word he dug up from Chaucer, for female).

Several NYC bloggers have picked up his terminology, which I question, because I don't think those terms are use in ornithology very often.