Fòram na Gàidhlig

Ann na Gàidhligh:
Ruairidh luath cinntinn, an-dràsta aon bliadhna, aon deug mìosan, agus ceithir deug làithean. An-diugh tha miann ann aodach, agus breacan e fhéin ann briogais ghoirid, ach an cneap.

Ruairidh is growing up fast, he's now one year, eleven months and fourteen days. Today he chose his own clothes and even managed to put on his shorts by himself, bar the button.

Or should that be 'anns a Gàidhlig' instead of 'ann na Gàidhlig'?

Yes, anns a' Ghàidhlig. Rinn tu glè mhath!

Beagan cheartachaidhean, mostly a bit of word order and expressions you can't know yet

Tha Ruairidh a' fàs suas gu luath, tha e aon bhliadhna, aon mhìos deug agus ceithir làithean deug a-nis. Thagh e fhèin a chuid aodaich an-diugh is chaidh leis a' bhriogais ghoirid a chur air leis fhèin ach am putan.

Agus carson "an chuid"?

It's the same thing as with "mo chuid Ghàidhlig" - you don't own all of Gaelic, you only have your version/part of it. For some reason, clothes are the same.

Seadh, ach bha mi den bheachd gum biodh sin "a chuid" (no "an cuid" nam biodh an t-aodach aige agus cuideigin eile).

Tha thu ceart! It should be "a chuid aodaich"