Mom passes away after giving birth to twins; GoFundMe set up for Colorado dad

May 29 was supposed to be one of the happiest days of Dustin Sisneros' life. He was finally going to meet his baby boy and girl.

But things took a terrible turn after his girlfriend Sara Sewald gave birth to healthy twins.

“They had mentioned that she had had a little bit of bleeding, you know, and they were going to do what they could to stop it. So, you know, I wasn’t really too nervous. They said not to worry, it’s kind of normal and we have it under control," Sisneros recalled.

It was a surgery she would never come out of.

Suddenly a single father of two and reeling from the loss of his longtime love, Sisneros sat down with 11 News reporter Ashley Franco to share his memories of Sewald and express his gratitude for the outpouring of support from the community.

"It was almost love at first sight," Sisneros said of meeting Sewald. "I waited just a little while to go ahead and ask her to be my girlfriend. But, from the moment we first hung out that night I knew that I really liked her and I could tell instantly that she had the biggest heart."

After three and a half years together, the couple learned they were going to become parents.

"When we found out it was twins it was kind of overwhelming but we were really excited for our blessings."

Months into the pregnancy, Sewald and Sisneros went to the doctor for a routine check-up. The doctor noticed swelling and immediately told the couple to go to the hospital. The next morning, Sewald went in for a C-section.

“We woke up that morning and we were both super excited to go into the delivery room. I gave her a big hug and kiss before she went into the delivery room. They took her in, and I went and got all of my scrubs on, and they took us into the delivery room ... it was the beginning of an amazing journey.”

Sewald delivered two healthy babies, Charlotte and Ryan. But then complications followed.

"They had to take her back into the ICU and feed her some blood and put her on oxygen. You know, they had sedated her and prepared for her surgery to get her you know back to health ... unfortunately, it was just a complicated surgery. It’s hard to ask a lot of the details about what had happened.”

Their children have remained in the hospital in the days since Sewald's death.

"I’ve been down to the hospital every single day. I’ve got to spend a lot of time with them," Sisneros said. "It just makes my heart happy whenever I see them. I go in there and I talk to them and they kind of -- they know my voice and they open their eyes and they’re just the most beautiful thing. Charlotte resembles Sara in so many ways."

He says he will never stop telling the twins about their mother.

"Every time I see them, I tell them their mommy loves them, and they either give me a smile so I know that she’s signifying that she’s watching and she’s in the room with us and she’s right there. It’s just so amazing. I’ll be sure her memory lives on forever."

Since Sewald's passing, friends of the couple set a GoFundMe account to help her partner and children during their time of mourning and beyond. Since setting it up, the fund has gone viral.

Sisneros and his parents, who are helping out, say they are overwhelmed by the support from people all over the country.

It’s just absolutely unbelievable, the love and support from all of the different states," Sisneros said. " ... We will use all of it and donate it after we’re done and make sure someone else will have what they need. That’s really the most important thing.”

to visit the GoFundMe account.