Staff at the Tweed Valley Osprey Project said the distraught male still stayed at the nest with fish for his mate but it was in vain as she never returned.
They said it is likely the recent wet and changeable weather would have made it too difficult for the chicks to survive without their mother.
Diane Bennett, osprey information officer for the project, said: "The death of the chicks has been a real shock to all those who have been following this osprey family for the last 10 years.
"There is glimmer of hope though. Although we can't confirm whether it is the same female, one has turned up and the male is very keen and has already been mating with her."