You may be looking for the character of the similar name, Altena.
Altina (オルティナ Orutina) is one of Ashera's Three Heroes who sealed Yune away in Lehran's Medallion about 780 years before the beginning of Fire Emblem: Path of Radiance. She is a beorc swordswoman who wielded both Alondite and Ragnell. She is the ancestor of Meshua, Yoram, Misaha, Micaiah and Sanaki, as well as the founder of Begnion.
It is said that Altina is the only person capable of awakening Yune through the Galdr of Release. However, the galdr can be sung by the firstborn of each generation of her descendants. Sanaki is believed to have this power at first; but it is revealed in Fire Emblem: Radiant Dawn that she is not the firstborn, but instead, she has an elder sister who does hold these powers. The true heir of Altina also bears the brand, suggesting that the power to sing the galdr of release actually belonged to Lehran, Altina's first husband and the biological father of her child.
The name 'Altina' evokes the Latin verb alo alere alui altum ('altum' is the past participle) which as a verb means 'to grow, support, rear, feed' and as an adjectival participle (altus, a, um) it means "high" or "deep".