Blackpool defender Eastham arrived at Whaddon Road in the first week of January and has so far made five league starts for Mark Yates` men.
The 19-year-old is enjoying his second loan spell with the Robins having made 20 outings for the club between December and May last season.
Meanwhile, striker Walsh has departed the Gloucestershire club after only one month on loan.
The Daggers frontman made just four substitute appearances due to the form of Wes Thomas and Jeff Goulding and, despite Yates wanting to keep hold of his services, is keen for more regular first-team football.
Source: PA
Source: PA