LDR Question

I really love my man. He is so amazing and we have been doing long distance for a year now. We pretty much have it down at this point but lately I feel like he's been really tense. He gets frustrated with his siblings so easily now and he used to be so patient with them. There are more little things that seem to have changed and I know he's just upset because it's hard for us to be apart so much. He doesn't get frustrated with me but I really just want to help him relax but it's really hard to do from 3,000 mile away. Any advice?