The Blackpool defender arrived at Whaddon Road in early January and has so far made six starts and one substitute appearance for the Robins.
Eastham, 19, spent six months on loan with Town last season, helping the club avoid relegation from League Two.
He has made two first-team appearances for Blackpool, both of which came at the start of the 2009/10 campaign.
Source: PA
Source: PA