Say hi to one of my Mangrove Gerygone (Gerygone levigaster) mums from the mud at the end of Orient Road. She's back on the job not so long after her last young one went whereever they vanish to. (Which means I have no idea why there are always three or four pairs amid their stretches of mangroves and no trace of yesterday's young in the wider area.)
Anyway, the gender giveaway is the divided breast plumage - from long sitting on the egg (in this case) or eggs (two sometimes, though often just one survivor) in the nest. Once the egg hatches, mum's old man will arrive with food. Perhaps a picture of them together will reveal little differences. We'll see.