After 12 years of dating and one year of marriage, high-school sweethearts Samuel and Penelope started trying to conceive. Both grew up in tight-knit families, and had long dreamed of having biological children together.  But when a year passed without a positive pregnancy test, the couple — who asked to use pseudonyms because they haven’t even told some relatives about their fertility experience — asked doctors what was going on.  “We were looking at everything,” Penelope told The Post. “They