WATCH: Even With DNA Evidence, Gay Texas Dads Still Denied Adoption Rights

After being denied the right to cross-adopt or be listed on their newborn twin's birth certificates, Texas couple Jason Hanna and Joe Riggs have begun making the media rounds to explain a situation they say they never expected to be in, and which they fear will leave their children vulnerable should one of them become absent.

In a SiriusXM interview on Wednesday, Hanna described how the couple has challenged the initial denial of their petition to be listed on their sons' birth certificates by submitting DNA proof that each man is biologically related to one of their sons. Despite this, their cross-adoption petitions were again denied, and the courts refused to remove the surrogate mother -- who is not biologically related to either boy, as they were conceived via an egg donor -- from the birth certificates.

"I went in very optimistic," Hanna told Tamron Hall in an interview with MSNBC's NewsNation. "We are the biological dads. We have the paperwork. And there's no reason we should not have full adoption rights to our own children."

In Texas, according to Hall, individual judges have a choice of whether to approve or deny the cross-adoption petitions of unmarried couples. Because the state does not have equal marriage, Hanna and Riggs -- despite being legally married in Massachusetts -- are not considered a legally married couple by Texas courts.

With the judge assigned to their case continuing to deny their parental rights, they now face the option of re-petitioning or taking the case to another judge.

The couple's convoluted situation is representative of what's wrong with U.S. family protection laws, according to Gabriel Blau, executive director at the Family Equality Council. In the same interview with Tamron Hall, he explains that nationally recognized equal marriage would alleviate some of the issues with cross-adoption that "patchwork" the U.S., but that even more reforms are needed to avoid leaving the adopted children of any couple, same-sex or not, at risk.

Watch the interview below.