Letter to Einstein from his son

Dear Papa,
Imagine, Tete can already multiply and divide, and I am doing geometetry (geometry) as Tete says. Mama assigns me problems; we have a little booklet; I could do the same with you then as well. But why haven't you written us anything lately? I just think: "At Easter you're going to be here and we'll have a Papa again."
Yours, Adu!

The letter was sent to Einstein from his older son Hans Albert (known as Adu) at 1915, when Einstein was working on his General Theory of Relativity. His younger son Eduard was known as Tete. For more details on Einstein and his personal life crisis at that time refer to www.time.com