Merging partitions in Debian

I have recently inherited someone else's problem with a linux server. This is one of those all in one debian based lamp setups. It recently ran out of storage and no one seems to know anything about linux in general here. I have managed to expand the drive in VMWare and created the partition as seen in the image below. The challenge is to merge the root partition /dev/sda1 with /dev/sda4. Note: the Start - End blocks are not back to back and I can't afford much downtime on this server. /dev/sda3 can probably be merged too but not important. UPDATED: df -h output UPDATED 2: fdisk -l output