here's randi kaye. >> reporter: it is the other question in the casey anthony trial. -- the fbi's dna tests ruled out george or lee anthony. but that didn't stop the defense from suggesting it during one of the most explosive moments of the trial. >> were you asked to conduct a paternity test for lee anthony as to caylee -- being the potential father of caylee anthony? >> jesse grund, casey anthony's ex fiance, isn't the father, either. >> i got a paternity test done to prove that i was not caylee's biological father. >> grund says a pregnant casey told him the baby was his. but when caylee was born less than seven months after the couple had met, he knew it wasn't true. even so, grund wanted to be a father to her. >> did you love little caylee like she was your own child? >> a piece of paper couldn't tell me not to love her like she was my daughter. >> reporter: but casey anthony told different things to different people. according to this deposition by brittany sheiber, an old friend, casey told brittany she didn't know who the father was. brittany goes on to say that casey's best f

here's randi kaye. >> reporter: it is the other question in the casey anthony trial. who was little caylee anthony's father? to answer that question, it's best to start with who we know it isn't. we know it's not casey's own father, george, nor her brother lee. the fbi's dna tests ruled that out. but that didn't stop the defense from suggesting it during one of the most explosive moments of the trial. >> were you asked to conduct a paternity test for lee anthony as to caylee -- caylee being the potential father of caylee anthony? >> reporter: jesse grund, casey anthony krae's ex we awn say isn't the father, either. >> i got a dna test to prove that i was not caylee's biological father. >> a pregnant casey told him the baby was his. but when caylee was born less than seven months after the couple had met, he knew it wasn't true. even so, grund wanted to be a father to her. >> did you love little caylee like she was your own child? >> a piece of paper couldn't tell me not to love her like she was my daughter. >> reporter: but casey anthony told different things to diffe

here's randi kaye. >> reporter: it is the other question in the casey anthony trial. -- the fbi's dna tests ruled out george or lee anthony. but that didn't stop the defense from suggesting it during one of the most explosive moments of the trial. >> were you asked to conduct a paternity test for lee anthony as to caylee -- being the potential father of caylee anthony? >> jesse grund, casey anthony's ex fiance, isn't the father, either. >> i got a paternity test done to prove that i was not caylee's biological father. >> grund says a pregnant casey told him the baby was his. but when caylee was born less than seven months after the couple had met, he knew it wasn't true. even so, grund wanted to be a father to her. >> did you love little caylee like she was your own child? >> a piece of paper couldn't tell me not to love her like she was my daughter. >> reporter: but casey anthony told different things to different people. according to this deposition by brittany sheiber, an old friend, casey told brittany she didn't know who the father was. brittany goes on to say th