Have you ever noticed that in English, many words beginning with gr- describe a complaining vocalization or an irritable disposition? Wiktionary offers the following definitions (among others):
Grunt: n. A short, snorting sound, often to show disapproval, or used as a reply when one is reluctant to speak.
Groan: n. A low, mournful sound uttered in pain or grief; a low, guttural sound uttered in frustration or disapproval.
Grumble: v. To complain.
Gripe: v. To complain; to whine.
Grizzle: v. (UK, slang) To whinge or whine.
Grouse: v. To complain or grumble.
Grumpy: adj. Unhappy, dissatisfied and/or irritable, a word which is particularly applied to babies and children or adults who are acting childishly.
Grump: n. A habitually grumpy or complaining person. v. To complain; to be grumpy.
Grouchy: adj. (originally US college student slang) Irritable; easily upset; angry; tending to complain.
Grouch: n. One who is grumpy or irritable. v. To be grumpy or irritable; to complain.
Growl: v. To utter a deep guttural sound, as an angry animal; to give forth an angry, grumbling sound.
Other unpleasant "gr" words include greed, grief, grimy, grisly, gritty, grotesque, grubby, gruesome, grudge, gruff, and maybe grunge. To be sure, there are lots of "gr" words that don't have any negative connotations. But still, this opening letter combination seems to bring more than its fair share of misery in its train. I don't know why this is. I'm just saying...