Stepfamily Realities 51 and 52 - Stepchild Adoption
Adoption is usually the only way a stepparent can gain legal parenting rights and responsibilities for their stepchild/ren. It's a highly emotional, complex decision which usually requires the informed consent of both of the child's bioparents, if living. The high majority of the hundreds of U.S. stepparents I've met did not legally adopt their stepkids.
Unless done from guilt, duty, pity, insecurity, and/or competition with someone, stepchild adoption is a powerful statement of a stepparent's re/marital and family commitment. Because it often increases the stepparent's family status, authority, and power, adoption can evoke respect and relief or significant resentments or fears (e.g. of status-loss) among kids, ex-spouses, and relatives.
The idea or the process of adopting a stepchild may cause significant loyalty conflicts and relationship triangles unless all affected people have honestly discussed their feelings, concerns and needs. Depending on many factors, stepkids may range from resistant to indifferent to excited. Last names; bequests and estate planning; child support, and stepfamily roles, alliances, loyalties, and prior legal parenting agreements may all change because of such an adoption.
Patience + effective communication + all adults accepting stepfamily identity and realities + effective strategies for resolving loyalty conflicts and relationship triangles + honest inclusion of all stepfamily members' feelings + partners debating "Is this best for our marriage (not just for the kid/s)" can help all co-parents make a healthy long-range decision on if and when to adopt. Getting qualified (stepfamily-aware) professional help to facilitate this complex, impactful process can be a high-return investment. Alert: legally adopting one or more stepchildren will probably not heal a troubled re/marriage or turn the stepfamily into a "traditional" biofamily!