Now, some viewers of the couple's YouTube channel are casting doubt on the authenticity of the couple's story – but Sam and Nia say they're focused on moving beyond the heartbreak.
"We basically decided we're not going to address anything negative that could come from this," Nia tells PEOPLE. "We have so much love and support, that's what we want to focus on … our minds don't be need to be filled with negativity. We don't want to spread hate, we want to spread love in this situation."
While some fans have rallied behind the family of four, wishing them love and offering words of comfort, others are questioning whether the pregnancy and subsequent miscarriage were nothing more than a publicity stunt.
Some also questioned how Nia knew she was having a girl – she refers to the baby as "she" in the miscarriage video. "My other two pregnancies early on, I felt what I was having, and I was right about both of them," Nia tells PEOPLE. "I just really had that feeling, of course we didn't know for sure."
Others probed the validity of the initial pregnancy test, as the father of two raced to the bathroom to use an overnight urine sample from the toilet to complete a pregnancy test and surprise Nia with the results. That video concludes with a follow-up positive pregnancy test taken by Nia – and garnered more than 11 million views.
Our tiny baby brought 10M views to her video & 100k new people into our lives. She turned our life around & brought us closer together.— Sam&Nia (@SamAndNia) August 9, 2015
Sam told PEOPLE his medical training made him certain of the signs of Nia's miscarriage.
"I'm a nurse so I know the signs of a miscarriage," he said. "The moment before it even happened, I started crying and when it actually happened [it was] just the biggest devastation our family has ever experienced. Her womb is so completely empty and I just know there's an emptiness in myself."
The pair say that from the time they learned of Nia's pregnancy to the miscarriage just days later, they didn't have a chance to see a doctor.
"We had just found out, literally, almost a whole day had gone before the miscarriage," says Nia.
Telling their eldest, now 5, about the loss was difficult.
"She was heartbroken, right away she understood. We told her the baby has 'Gone to Jesus,' " says Nia, adding that their younger child is nearly 2 and wasn't really aware of the situation.
Both Sam and Nia have expressed a strong desire to expand their family. They say if Nia becomes pregnant again, they'll announce it just as quickly.
"We don't regret it at all, especially considering miscarriage is such a taboo subject. A lot of people feel they need to wait to announce their pregnancy but when you're pregnant, you're pregnant," said Sam. "It shouldn't be something people need to hide."
Miscarriage is the loss of a pregnancy before 20 weeks and it's rather common. It happens in 15 percent of known pregnancies, according to the American College of Obstetricians and Gynecologists. Bleeding and clots are common signs of miscarriage, as are cramping of the abdomen and back pain.
Sam and Nia add that they believe it's important to talk about miscarriage to help ease the pain of those going through it and to remind them that they're not alone.
"We realized that [talking about miscarriage] was an issue and one of the reasons we decided to announce it. No we don't regret it at all and next time we'll do the exact same thing."