Neighbours dog

[Hamzter]

The neighbours dog has been barking constantly for the past 5 hours, driving me nuts, I think they may have gone on holiday and left the dog in the house, I'm a bit concerned because it sounds a bit in distress! Is there anything I should do? Or is it normal for dogs to bark a lot when left alone?

 

[Hamzter]

The neighbours returned in the end, pretty late, but they hadn't gone on holiday. Turns out they've only had the dog a couple of days and it was just a bit upset at being alone, but all is well now. The dog's cool also