The Adipose First Family was an Adipose family.
At some point before 2009 they had lost their nursing planet, and had contracted with Matron Cofelia to seed the Earth. This was in violation of Galactic Law as Earth was a Level 5 planet. At least one Nursery Ship had been dispatched for this purpose.
The operation was to produce several million offspring. It was aborted when the Tenth Doctor intervened, and only about ten thousand young were birthed and evacuated. Agents of the First Family aboard the Nursery Ship killed Matron Cofelia right before their departure from Earth, as they wanted to get rid of their accomplice. (TV: Partners in Crime)