Her singing voice pinched a bit as she feels her contraction come... Well, it's been happening for the whole day, she surely knows what's coming next.
And of course, he noticed that too. He's always being extremely careful about her, not even a single ache can hide away from his eyes.
But seeing her still singing, smiling while contraction hits her, trying to make his day wonderful, he doesn't disturb her, he knows she can maintain.
Eventually, the birthday song has ended, he scooped her up into his arms and blew the candle.
"Thank you, sweetie," He said sincerely, he can surely tell how much she likes him, she would bear the aches and pains for him.
But oppositely, she doesn't know a thing, even though seeing her having contractions makes him worry, that's the best gift for him today.
"Let's unbox the gifts, yeah? I can't wait to see~"
"... Ah, master, alright, but it's not going to be that quick, you know... Hnnnngh...!"