Pinako Rockbell

Pinako Rockbell is a surgeon and weaponsmith living and working in the town of Resembool in the eastern region of Amestris. Mixing her two specialties, Pinako is also a prominent automail engineer and presumably the founder of Rockbell Automail, a family-run automail atelier within the town. Pinako also happens to be the grandmother of Winry Rockbell as well as the neighbor and close family friend of the Elrics - Van Hohenheim, Trisha, Edward and Alphonse. As Winry's only remaining blood relative after the death of her parents, and the closest adult to the Elric brothers after their mother's passing and their father's disappearance, Pinako acts as caretaker to the three youngsters, training Winry in automail engineering and serving as Ed and Al's home base whenever they return to Resembool.

History
Pinako is likely a native resident of Resembool, as she appears in pictures in the town as far back as 1866, by which time the youthful woman had made a jovial drinking companion of the man called Hohenheim. She seems to have had a rather lively past as multiple photographs depict her partying jovially with several of the town's inhabitants and, according to Dominic Lecoulte of Rush Valley, had gained notoriety (or perhaps infamy) as an engineer known by the moniker "Pantheress of Resembool". It is unknown by whom she married into the Rockbell family, but she appears with her late husband in photographs soon after having befriended Hohenheim and gave birth to her son Urey in 1873. At some point in the 1890s, Pinako was instrumental in introducing Hohenheim to Trisha Elric, another of Resembool's young women, culminating in the two's union.

In the Manga
Pinako Rockbell is one of Amestris' most famous automail engineers and considered an independant - and, to some, even scary - woman. It's said that, during her young age, she travelled all over the country in order to perfect her abilities, but it's not clear how she came to live in Resembool, nor how she came to have Urey or who's his father.

She had befriended Van Hohenheim when she was still young - she knows him, at least, since 1866 - and always seems to help and care for him, even though she knows and seems to be slightly frightened of his secret of never aging.

She first appeared in Chapter 9 of the manga, when Ed and Major Armstrong came to visit, and she and Ed immediately got into an argument about their height. In later chapters she makes the most prominent appearance when Hohenheim came to visit, and then when Ed decided to dig up the remains of their failed transmutation, and was saddened to watch Ed come to the realization that the corpse did not resemble his mother in any way.

Later, everytime they have something to solve in Resembool, Pinako seems to help. Although she might not seem very protective towards Winry, Ed and Al, it can be implyed she believes those children have to 'live their own experience' and she's confident they'll call on her whenever is necessary. She always complains to Winry she never calls from Rushvalley, but also understands and supports her decision of pursuing training in automail engineering.

She also seemed to realise the nature of Ed and Winry's relationship long before them, but doesn't seem to have any objections, being rather amused of their constant fighting.

Trivia

 * In an omake strip, Hiromu Arakawa revealed that Pinako's unique, rigid ponytail is so shaped because she hides Nattō beans therein. While this is obviously meant to be a joke on Arakawa's part and not to be counted as canon, the author does reveal that she had designed Pinako's hair specifically with that joke in mind.
 * It was revealed in volume 5, that she was feared by an automail engineer named Dominic, and was known as 'The Pantheress of Resembool'. (much to the shock of Ed, Winry, and Al)