Praise be to Allah.
Whilst we appreciate the emotional attachment and feelings that your family has, the situation that you describe does not justify your breaking the prohibition on taking pictures, so long as these pictures are printed, drawn or engraved, as we have already stated in question # 365. Some scholars allow impermanent pictures which do not last, such as pictures stored in a computer’s memory which appear in the screen and then disappear. If the problem can be solved by storing the picture (in .jpg format, then sending it via the Internet, so the picture is not permanent), then this is permitted according to some scholars.
We would also like to point out that true memories reside in the heart, and that many generations of mankind have come and gone who felt love for one another and did good to one another, and a grandfather would love and pray for his grandchild without ever seeing him. May Allaah reward you with good for your question.