So here it is: the full scene from Quantum Leap in which Sam sings "Imagine" to his little sister. Very touching and moving! And I must say this little girl playing his sister (Olivia Burnette) is amazing, how her expression changes from curious amazement to sad realisation (does this sentence makes any sense? Well, sounds good..)!
(And, of course, as always: No copyright infringement intended, no profit made!)