However, if they have been vomiting numerous times, then the blood could be due to irritation of the stomach and intestines.
1	However	however	ADV	RB	_	18	advmod	18:advmod	SpaceAfter=No
2	,	,	PUNCT	,	_	18	punct	18:punct	_
3	if	if	SCONJ	IN	_	7	mark	7:mark	_
4	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	7	nsubj	7:nsubj	_
5	have	have	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	7	aux	7:aux	_
6	been	be	AUX	VBN	Tense=Past|VerbForm=Part	7	aux	7:aux	_
7	vomiting	vomit	VERB	VBG	Tense=Pres|VerbForm=Part	18	advcl	18:advcl:if	_
8	numerous	numerous	ADJ	JJ	Degree=Pos	9	amod	9:amod	_
9	times	time	NOUN	NNS	Number=Plur	7	obl:tmod	7:obl:tmod	SpaceAfter=No
10	,	,	PUNCT	,	_	18	punct	18:punct	_
11	then	then	ADV	RB	PronType=Dem	18	advmod	18:advmod	_
12	the	the	DET	DT	Definite=Def|PronType=Art	13	det	13:det	_
13	blood	blood	NOUN	NN	Number=Sing	18	nsubj	18:nsubj	_
14	could	could	AUX	MD	VerbForm=Fin	18	aux	18:aux	_
15	be	be	AUX	VB	VerbForm=Inf	18	cop	18:cop	_
16	due	due	ADP	IN	_	18	case	18:case	_
17	to	to	ADP	IN	_	16	fixed	16:fixed	_
18	irritation	irritation	NOUN	NN	Number=Sing	0	root	0:root	_
19	of	of	ADP	IN	_	21	case	21:case	_
20	the	the	DET	DT	Definite=Def|PronType=Art	21	det	21:det	_
21	stomach	stomach	NOUN	NN	Number=Sing	18	nmod	18:nmod:of	_
22	and	and	CCONJ	CC	_	23	cc	23:cc	_
23	intestines	intestine	NOUN	NNS	Number=Plur	21	conj	18:nmod:of|21:conj:and	SpaceAfter=No
24	.	.	PUNCT	.	_	18	punct	18:punct	_
