The `Fright Night` star has legally become the father of 10-year-old Tyler, his wife Georgia Moffett`s child from a previous relationship and he is thrilled he has been able to officially become his father.
Speaking on the Christian O`Connell breakfast show on Absolute Radio, David - who has a baby daughter Olive with Georgia - said: "The baby is nearly a year and I adopted my wife`s boy last year so I`ve become a father twice with in a year - that`s something of a record isn`t it? I hope he`s listening."
The 40-year-old actor first met the 27-year-old actress when she starred opposite him in `Doctor Who` episode `The Doctor`s Daughter` in 2008 when he played the Time Lord.
Georgia`s father is Peter Davison, who portrayed the Fifth Doctor in the 80s.
The couple tied the knot last New Year`s Eve (31.12.11) in an intimate ceremony in London before throwing a huge party at the Globe Theatre, which was attended by celebrity guests including Stephen Fry and Will Mellor.
Following Olive`s birth last year, Christian revealed his good friend David was "smitten" with his baby daughter.
He said: "A couple of you have been asking on Facebook how DT is, DavidTennant, I swapped texts with him over the weekend. He is smitten with his new baby daughter.
"I know from his texts he`s enjoying it but it is utter chaos even with his sonic screw driver he`s still got to change the nappies."