Possessive pronouns show manual agreement with the possessor. During their production, they are directed toward the locus in space associated with the referent functioning as possessor. The screenshots below show the spatial agreement between possessor and possessive pronoun. As shown by the indexes associated with the glosses, the two signs are co-referential.
pietroa poss3a
Note that such manual agreement is visible when the possessor is realised by a sign articulated in neutral space. If the possessor is represented by a body-anchored sign, such as maria below, spatial agreement does not occur.
maria poss3
In this case, the possessive pronoun shows spatial agreement with an arbitrary locus in space associated with the body-anchored sign.