Any conveyance of real estate made by the grantor to himself, herself or itself and another or others, either as joint tenants with right of survivorship or as tenants in common, shall, if otherwise valid, be as fully effective to vest either an estate in joint tenancy with right of survivorship or an estate as tenancy in common, as the case may be, in such real estate, in the grantees named, including the grantor, as if the same had been conveyed by the grantor therein to a third party and by such third party to said grantees.