Any way you cut it, wrong decisions were made. Yes, there was a potential safeguarding issue for their child if both parents became incapacitated. But that was not the case at the time. PM implies journey was made with his approval. Wrong call. Sends the wrong message. Far better for him to have ordered DC to stay put and promise provision of care IF NEEDED. Not sure about the barnards castle sighting. Fake news??
That being said my son in law and daughter are both front line NHS. If they had got ill I would have driven from Wales to Yorkshire to rescue grandchildren, lockdown or no.