The final "r" in "bràthair" sounds like a "d" or "t". I've noticed that in other similar-ending words. Is that common in some dialects or is it an idiosyncratic pronunciation of the reader?
It's a "slender r" - the i preceding it makes it slender. The slender r sound varies, but is often like a "th" sound, sometimes very light and unvoiced, sometimes heavier and voiced - but not like anything you're likely to think of as an English r sound.
Does little here also count for age, or does beag stick to describing physical size? In English little works for both, but I get other languages might not do that same.