Your babies' eyes may open and blink at week 26 and retinas are beginning to form.

The air sacs of the lungs are taking shape this week as well.  Even though the lungs are still growing, they still have to mature for babies to be able to breath without help.

You may have felt your babies' hiccups by now.

Get yourself familiarize with the signs of premature labour, just in case your twins decide for an early arrival.