Opinions on this seem to differ with plenty of anecdotal information on either side. Indeed it doesn't appear that there is any concrete evidence.
There does seem to be some consensus however that it depends on the dog and how long they were together.
Steven R. Lindsay, author of the "Handbook of Applied Dog Behavior and Training," suggests they can. In his writings, Lindsay suggests that a dog can recognize his parents and siblings, and even humans from early interactions, provided they are together during the critical socialization phase from week three of life through week 16.
Petful
In your case your beagle was separated at only 8 weeks, and then underwent a lot of new experiences immediately afterward. Most likely it was too early for them to form enough of a bond to remember.