I don't know how true it is but apparently it's the egg that provides the energy for you to grow for the first three days of your development. After that the rest of the process is all up to you. This apparently helps to explain why some embryos go well for the first two or three days and then stall in their development, or conversely, you get some which seem to go very slowly but then suddenly start to play catch up a couple of days after conception.
Obviously, the fact that you made it to blastocyst stage shows that you had enough energy. Hopefully my eggs did their bit and then you were able to take over and keep going.
The next big test is when we take you out the freezer. You need to summon on those reawakened energy reserves and pick up where you left off. If you're reading this letter then you know that you did just that and I believe in you enough to actually write this series of letters, so I'm sure that you'll do just fine.
I hope that you never lose that momentum which carried you for those first five days of life. I hope that you'll always be active in some way, either physically or mentally. Searching for new activities, new knowledge, new horizons.
And I sincerely hope that I have enough energy to keep up with you!
So if it ever seems like your old dad and I are moving a little bit too slow, just remember, our spark of energy has been running for a lot longer than yours. We need more time to recharge our batteries!
All my love,