Dear Mrs Walker-Huntington, My husband is a resident of the United States (US). We got married in 2015. He was told by someone who works at the embassy that he cannot file for my 15year-old daughter because she is not his biological child. Kindly let me know if this is so.
Your email was not clear, but I am going to answer, assuming that you are telling me that your husband is filing for you and your daughter.
Since you married your husband before your daughter was 18 years old, she is considered a stepchild for immigration purposes, and your husband can file for her to obtain US residency. Whenever there are non-biological children in a relationship and the adults marry before the children are 18, a step-parent relationship is established for immigration purposes. This step-parent relationship allows the step-parent to file an immigrant petition for the child, and it also allows the child (when eligible) to file an immigrant petition for the parent.
As a green-card holder filing for his spouse, your husband does not need to file a separate petition for your daughter. She is eligible to ‘ride’ on your petition in the beginning, and when the filing gets to the National Visa Center, it will split into two files. However, if your husband is in the process of becoming a US citizen within the next year or so and plans to upgrade the filing to that of the spouse of a US citizen, he should file two separate petitions for you and your daughter. There is a difference between a US citizen and a greencard holder filing for their spouse and child or stepchild.
Currently, the petition for the spouse and minor child of a green- card holder is taking about two years to receive an interview; and the spouse and minor child of a US citizen takes nine months to a year to interview at the US embassy in Kingston.