The court may make partition of all or any portion of the land included in the petition of which the parties thereto are co-tenants; but if all of the common land is not included in the petition, the court may, upon request of any party thereto, seasonably filed, cause any other part of the common land to be included, unless a petition for partition thereof is pending in another county or in the land court.
Mass. Gen. Laws ch. 241, § 4